Microblogging service Twitter expanded their portfolio today, introducing a new interface optimized for mobile phones. Aiming for an improved experience on Android, iPhone, webOS and Nokia S60 platforms, the interface was designed with the Twitter API. Most features from the site have been included, such as reply, retweet, favorites, mentions and direct messages. Following, search and other functions are also present.

The interface will eventually replace the standard mobile site for Twitter, though it is still under development. Users of the BlackBerry browser and some other phones have reported issues with the new site. Ultimately, the new interface may supplant standalone applications on phones as well, which would make Twitter even more portable.

This latest development comes as Twitter seeks to turn a profit, introducing paid accounts to their business model. While their financial future may be in question, many sites and businesses are embracing the service, and being more accessible on mobile devices will help fuel that.